Polyurethanes are a versatile class of polymers that are used in a wide range of applications, for example: plastics, elastomers, flexible or rigid foams, gaskets and seals, coatings, fibers, and adhesives. Polyurethanes can be made by combining polyols and polyisocyanates, such as diisocyanates, optionally including chain-extenders such as diols, diamines, and the like. Polyols and polyisocyanates are typically derived from petroleum-based materials. There has been work in recent years to replace the petroleum-derived polyols with polyols derived from non-petroleum sources, such as vegetable oil, soybean oil, and castor oil. However, little attention has been paid to development of polyisocyanates from renewable non-petroleum sources.